Adjustable triangle.



PATENTBD JULY 30, v1907.

- H. o. FIELD & c. MO'RK.

- ADJUSTABLE TRIANGLE. APPLICATION FILED APR. e, 1901.

A TTORNE Y5 INVENTOR' HAROLD O. FIELD AND OHRISTEN MORK, OF MOSCOW, IDAHO.

ADJUSTABLE TRIANGLE Specification of Letters Patent.

Patented July 30, 1907.

Application filed April 6,1907. Serial No. 366,790.

To all whom it may concern:

Be it known that we, HAROLD O. FIELD and Cums- TEN Monk, citizens of the United States, residing at Moscow, in the county of Latah and State of Idaho, have invented a new and useful Adjustable Triangle, of which the following is a specification.

This invention relates to adjustable triangles for use by draftsmen.

The invention is more particularly designed as an improvement upon a device described and claimed by us in an application filed May 7, 1906, Serial No. 3l5,694, and its object is to provide a triangle having movable members adapted to be adjusted to form angles of different degrees, said degrees being visually indicated by a graduated sector and an index cooperating therewith.

A still further object is to provide novel means whereby the members of the triangle can be held in any position to which they may be adjusted.

With these and other objects in view the invention consists of certain novel features of construction and combinations of parts which will be hereinafter more fully described and pointed out in the claims.

In the accompanying drawings is shown the preferred form of the invention.

In said drawings: Figure 1 is a plan view of a triangle constructed in accordance with the present invention, said triangle being shown adjusted out of its normal position; Fig. 2 is a section on line 2-2, Fig. 1; and Fig. 3 is a section on line 33, Fig. 1.

Referring to the figures by characters of reference, 1 is the base of the instrument, the same being provided with an arm 2 extending at a right angle from one end thereof and having a beveled end 3 formed with a projection 4. The other end of the base is gradually reduced in width toward that end thereof farthest removed from the arm 2 as shown at 5, said base therefore coming to a point constituting the apex of the triangle. A strip 6 is disposed adjacent the base 1 and has a gradually tapered end portion 7 similar to the tapered portion 5 of the base 1, said tapered pertion terminating in a point which constantly contacts with the point of the base 1. The other end of strip 6 is beveled as shown at 8 and has a recess 'Qadapted when the triangle is collapsed to its smallest extent to receive the projection 4.

Recesses 10 are formed in the base 1 and the strip 6 near the points thereof and within these recesses are pivoted links 11 which are connected together to form a toggle. Recesses 12 are also formed in the ad joining faces of the base 1 and strip 6 near the broad ends of the reduced portions 5 and 7 respectively and 7 within these recesses are pivoted links 13 which are in turn pivotally connected as at 14 so as to form a toggle. The links 11 and 13 are proportioned so as to maintain the points of the two members 1 and 6 constantly in contact while the toggles formed by said links are being extended or folded.

A connecting link 15 is connected to the pivot 16 of the links 11 and is also pivotally connected to one of the links 13, as shown at 17, the distance from said pivot 17 to the adjoining pivot of the link 13 being equal to the length of one of the links 11. Another connecting strip 18 is connected to the links 1121.1; 16 and is pivoted to the other link 13 as shown at 19, the pivot 19 being disposed the same distance from the adjoining pivot of link 13 as the length of a link 1].. This strip 18 has a sector 20 formed therewith and provided with a slot 21, which slot is concentric with the pivot 22 of an index 23 mounted on the sector.

As shown particularly in Fig. 2 the inner edge of the sector is beveled as shown at 24 and is overlapped by a lug 25 extending upward from the index there being a lug 26 upon said index which travels within the slot, 21. One end of the slot is enlarged as shown at 27 so as to permit the lugs of the index to be disengaged from the sector when desired. An. arm 28 is pivotally connected to the connecting link 15 and to the index so that whenever the two members of the triangle are adjusted toward or from each other said link 15 will cause the arm 28 to swing the index on its pivot to indicate any one of a series of graduations adapted to be placed upon the sector. A link 29 is pivotally connected to the sector and to a sleeve 30 through which extends an adjusting screw 31. This adjusting screw is mounted to rotate in a recess 32 in base 1 and has a milled head 33 whereby said adjusting screw can be readily rotated. A recess 34 is formed in the base 1 to receive the link 29, and a portion of the sector and its index, and another recess 35 is formed in the strip 6 to receive a portion of the sector.

It is thought that the operation of the parts herein described will be clearly understood from the foregoing description when read in connection with the accompanying drawings.

When the screw 31 is rotated in one direction by re volving the head 33, the sleeve 30 is moved longitudinally along the screw and causes link 29 to pull or push upon the sector so as to cause a corresponding movement of the two toggles which will either be extended or folded according to the direction in which the sleeve 30 is moved. This will result in the changing of the angle of the two parts 1 and 6 without, however, causing the points of said members to move out of contact. This movement of the parts will cause link 15 to pull on the arm 28 and the index 23 will be swung upon its pivot until the end thereof will point to that graduation on the sector designating the angle at which the device is set. When the triangle is folded to its smallest extent the toggle 11 becomes entirely concealed within the recesses 10 and the balance of the mechanism becomes seated within the recesses 12, '34 and 35. The projection 4 when seated in the recess 9 positively locks the endof the arm 2 and the adjoining end of the member 6 together.

What is claimed is:

1. In an instrument of the character described the combination with a base, an adjustable strip connected thereto, toggle connections between the base and strip,

and links connecting the toggles; of a sector upon one of the links, an index pivoted upon the sector, and an arm pivotally connected to said indexand the otherlink.

2. An instrument of the character described comprising a base, an adjustable strip, toggle connections between the base and strip, link connections between the toggles, means for actuating the toggles, and means operated by the movement of the toggles for indicating the angle of the strip to the base.

An instrument of the character described comprising a base, an adjustable strip; said base and strip having unattached pointed ends constantly in contact, toggle connections between the base and strip, link connections between the toggles, revoluble actuating means, and means for transmitting motion therefrom to the toggles to adjust the strip.

4. An instrument comprising a base, an adjustable strip, said base and strip having unattached pointed ends constantly in contact, toggle connections between the base and strip, link connections between the toggles, a sector upon one of the links, an index, means actuated by the movement of the toggles for moving the index upon the sector, revoluble actuating means, and means for transmitting motion therefrom to the toggles.

5. An instrument of the character described comprising a base, an adjustable strip, said base and strip having pointed unattached ends constantly in contact, toggle connections between the base and strip, link connections between the toggles, a slotted sector upon one of said links, an index pivotally mounted upon the sector, projections upon the index engaging the slotted portion of the sector, means operated by the movement of the toggles for actuating the index, revoluble actuating means, and means for transmitting motion therefrom to the toggles.

6. An instrument of the character described comprising a recessed base, a recessed strip, said base and strip having unattached pointed ends constantly in contact, toggle connections between the base and strip, link connections between the toggles, a sector carried by one of said links and adapted to be seated in the recesses, an index carried by the sector, and means operated by the movement of the toggles for actuating the index.

In testimony that we claim the foregoing as our own, we have hereto affixed our signatures in the presence of two witnesses.

HAROLD O. FIELD. CHRISTEN Moan.

Witnesses I-I. MnLGAnD,

P. TEUSCI-IEL. 

